docs: def plot_labels(ax, label_fontsize=14,
                  xlabel=None, xlabel_arg=None,
                  ylabel=None, ylabel_arg=None,
                  zlabel=None, zlabel_arg=None):
      """Sets the labels options of a matplotlib plot
  
      Args:
          ax: matplotlib axes
          label_fontsize(int): Size of the labels' font
          xlabel(str): The xlabel for the figure
          xlabel_arg(dict):  Passsed into matplotlib as xlabel arguments
          ylabel(str): The ylabel for the figure
          ylabel_arg(dict):  Passsed into matplotlib as ylabel arguments
          zlabel(str): The zlabel for the figure
          zlabel_arg(dict):  Passsed into matplotlib as zlabel arguments
      """
      xlabel = xlabel if xlabel is not None else ax.get_xlabel() or 'X'
      ylabel = ylabel if ylabel is not None else ax.get_ylabel() or 'Y'
  
      xlabel_arg = dict_if_none(xlabel_arg)
      ylabel_arg = dict_if_none(ylabel_arg)
  
      ax.set_xlabel(xlabel, fontsize=label_fontsize, **xlabel_arg)
      ax.set_ylabel(ylabel, fontsize=label_fontsize, **ylabel_arg)
  
      if hasattr(ax, 'zaxis'):
          zlabel = zlabel if zlabel is not None else ax.get_zlabel() or 'Z'
          zlabel_arg = dict_if_none(zlabel_arg)
          ax.set_zlabel(zlabel, fontsize=label_fontsize, **zlabel_arg)